While many people simply think that exhaustion is counteracted with a good night of sleep, the effects that the activity has on memory should also be remembered too, according to a leading doctor. Answering questions for the readers of the Arizona Daily Sun, Dr Robert Rosenberg gave recommendations to a student at a local community college, who queried if it was true that sleep could enhance exam results if used correctly. Dr Rosenberg asserted that a good night of sleep has been proved to improve memory consolidation. He pointed to a recent study where subjects were told they were going to be tested the following day on what they had been taught; those that slept for longer did much better than others exposed to the same information who rested for less time. "The conclusion of the study was that after a good night's sleep, people remember information better when they know it will be useful in the future," the doctor added. "The findings suggest that the brain evaluates memories during sleep."